Moving Forward What does this mean for the Medical Physicist and the Imaging Community?

Transcription

1 Moving Forward What does this mean for the Medical Physicist and the Imaging Community? John M. Boone, Ph.D., FAAPM, FACR Professor and Vice Chairman of Radiology University of California Davis Medical Center Chairman, AAPM Science Council Chairman, ICRU * committee on CT Image Quality & Dose *International Commission on Radiological Units and Measurement

2 Moving Forward: National / International Activities Education and Training Clinical: What can we really do? Regulations, Accreditation, Certification

3 Moving Forward: National / International Activities Education and Training Clinical: What can we really do? Regulations, Accreditation, Certification

4 Science Council Imaging Physics Committee CT subcommittee TG-111 TG-200 TG-xxx Therapy Physics Committee Research Committee Technology Assessment Committee

5 industry FDA industry industry Robert L. Dixon, Ph.D., Chair of TG 111 FDA industry industry consortium

6 CT dose measurement techniques have not kept pace with CT technology TG mm CTDI = D() z dz nt 50mm dose old new position

7 CT phantoms have not kept pace with CT applications or acquisition modes TG-200 Phantoms for CT Phantom images courtesy of various web sites, Dr. Cynthia McCollough, and Dr. Robert Dixon L (C 5 O 2 H 8 ) n (C 2 H 4 ) n H 2 O Length Shape Composition Diameter

8 TG-xxx Pediatric CTDI w

9 ICRU Patient Dose Assessment and Image Quality in Computed Tomography

10 ICRU CT phantom and analyses contrast dosimetry spatial resolution (MTF) contrast resolution (NPS) MTF NPS

11 ICRU CT phantom evaluation Old Era New Era phantom complicated simple analysis MTF( f ) = 2πifx LSF( x) e dx LSF( x) dx simple complicated results perfunctory useful & quantitative

12 Historical CT dose evaluation

13 ICRU CT beam evaluation

14 National / International Activities Dose Reporting (ACR, etc) Reference Doses (NCRP) Dose Information in DICOM header

15 Moving Forward: National / International Activities Education and Training Clinical: What can we really do? Regulations, Accreditation, Certification

16 Leidholdt Bushberg Seibert Boone Traditional Books Walter Huda Bill Hendee Russ Ritenour

17 Annual Meetings in Radiology Societies and Focused Courses

18 76% of you are Medical Physicists Radiologists and Technologists don t design CT scanners, MP s do Medical Physicists must take the lead in CT and CT Dose Education

19 Medical Physics CT experts Industry Radiologists Technologists CT novice

20 The dose information was there on the CT scanner

21 GE VCT (1) GE VCT (2) GE Lightspeed 16 Toshiba Aquilion Siemens Definition GE Discovery Ceretom UC Davis Medical Center Main Hospital Siemens Sensation 64 Placer Center for Health Siemens AS+ Ellison Ambulatory Care Center 9 CT scanners only two are the same model

22 Patient: Ann Smith DOB: Accession Number: ABCDEF Referring Physician: Dr. Alan Jones Technologist: Alison Omega Hansley This scan Typical scan Abdomen Pelvis The parameters selected will result in a CT dose that is above the 75 percentile for this examination Do you want to proceed? kvp: 120 ma: 600 Rotation time: 0.50 sec Pitch: 0.95 CTDIvol: 33 mgy Length: 32.5 cm DLP: 1072 mgy cm RECON FILTER: xxx 64 x 1.00 mm Delivery: PACS 1 SCAN

23 Patient: Ann Smith DOB: Accession Number: ABCDEF Referring Physician: Dr. Alan Jones Technologist: Alison Omega Hansley This scan Typical scan Abdomen Pelvis kvp: 120 ma: Rotation time: 0.50 sec Pitch: 0.95 CTDIvol: mgy Length: 32.5 cm DLP: mgy cm RECON FILTER: xxx 64 x 1.00 mm Delivery: PACS 1 SCAN

24 Training Modules: MITA Medical Imaging and Technology Alliance VENDOR 1 VENDOR 2 VENDOR 3 VENDOR 4 MODEL A MODEL A MODEL A MODEL A MODEL B MODEL B MODEL B MODEL B MODEL C MODEL C MODEL C MODEL C MODEL D MODEL D MODEL D MODEL D MODEL E MODEL E MODEL E MODEL E

25 AAPM MITA

26 Moving Forward: National / International Activities Education and Training Clinical: What can we really do? Regulations, Accreditation, Certification

27 Cynthia McCollough, Ph.D. Mayo Clinic Rochester, Minnesota (N=28) Dianna Cody, Ph.D. MD Anderson Cancer Center Houston, Texas (N=36)

28 University of California Davis Medical Center, Department of Radiology, Sacramento, California John M. Boone, Ph.D. J. Anthony Seibert, Ph.D. Dr. Ramit Lamba CT doc Chief of Computed Tomography

29 CT Protocol Development at UC Davis (on limited budget with few participants) Department of Radiology Radiation Use Committee Health Physics Program

30 Monitoring local CT utilization CT use by age and gender N = 282,530

31 Monitor CT scans per patient mean = 2.88

32 Physicist Evaluation of CT Perfusion Protocols 1. Meet with Neuroradiologists techs administrators 2. Identify all scanners used for CT perfusion 3. Check CT perfusion protocols and evaluate dose (<500 mgy) 4. Lock down scanner security (passwords) 5. Heighten awareness of high dose CT techniques to techs 6. Scrutinize all CT Angiography protocols 7. Evaluate CT technologist training / CT certification (52% CT)

33 Physicist Evaluation of Pediatric Protocols Verify that CT techs are using the pediatric dose protocols (manual protocols)

34 CT protocol book (Lightspeed 16) Optimize CT protocols for all scanners GE VCT Siemens Definition Siemens Sensation 64 Siemens AS+ Toshiba Aquilion

35 ImPACTscan.org CTDI = CTDI CTDI w CENTER EDGE

36 CT protocol book (Lightspeed 16) mas values to match CTDI w of GE 16 at 100 mas

37 Other Considerations: Collimation Width Gantry Rotation Time Table Speed (ie. Pitch) Timing for Contrast Bolus Reconstruction Filters Window / Level Settings

38 Moving Forward: National / International Activities Education and Training Clinical: What can we really do? Regulations, Accreditation, Certification

39 Regulations

40 SB 1237 would require that on all imaging procedures involving ionizing radiation the provider would be required to indicate or note the specific radiation dose on the patient s film. CRS has also advocated the inclusion of a delayed mandate for accreditation of CT units in both hospital and freestanding settings that would parallel the Medicare requirement beginning in Regulations

41 Accreditation

42 Radiologist Medical Physicist CT Technologist ABR Certified ABR Certified ARRT (CT) Certified Certification

43

44 Moving Forward What does this mean for the Medical Physicist and the Imaging Community? John M. Boone, Ph.D. Professor and Vice Chairman of Radiology University of California Davis Medical Center